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Reed EK, Smith KA. Using our understanding of interactions between helminth metabolism and host immunity to target worm survival. Trends Parasitol 2024:S1471-4922(24)00135-1. [PMID: 38853079 DOI: 10.1016/j.pt.2024.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 05/10/2024] [Accepted: 05/12/2024] [Indexed: 06/11/2024]
Abstract
Helminths can adapt to environmental conditions in the host, utilising anaerobic processes like fermentation and malate dismutation to produce energy from carbohydrate. Although targeting carbohydrate metabolism is an established therapeutic strategy to combat helminth infection, questions remain over the metabolic pathways they employ as adults to survive and evade host immunity. Helminths also use amino acid, polyunsaturated fatty acid (PUFA), and cholesterol metabolism, a possible strategy favouring the production of immunomodulatory compounds that may influence survival in the host. Here, we discuss the significance of these differing metabolic pathways and whether targeting of helminth metabolic pathways may allow for the development of novel anthelmintics.
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Affiliation(s)
- Ella K Reed
- Cardiff School of Biosciences, Cardiff University, Cardiff, UK
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2
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Imajo M, Norikane T, Yamamoto Y, Maeda Y, Saitoh K, Kato K, Soga T, Okano K, Nishiyama Y. Relationship between [ 18F]FDG PET/CT and metabolomics in patients with colorectal cancer. Metabolomics 2022; 18:91. [PMID: 36367606 PMCID: PMC9652241 DOI: 10.1007/s11306-022-01952-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 10/30/2022] [Indexed: 11/13/2022]
Abstract
INTRODUCTION Advances in metabolomics have significantly improved cancer detection, diagnosis, treatment, and prognosis. OBJECTIVES To investigate the relationship between metabolic tumor volume (MTV) using 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET)/ computed tomography (CT) and metabolomics data in patients with colorectal cancer (CRC). METHODS The metabolome in tumor tissues was analyzed using capillary electrophoresis time-of-flight mass spectrometry in 33 patients with newly diagnosed CRC who underwent FDG PET/CT before treatment and had tumor tissue post-surgery. Based on the FDG PET data, MTV was calculated and was dichotomized according to the median value, and tumors were divided into low-MTV and high-MTV tumors. Metabolomics data were compared between the low-MTV and high-MTV tumors. RESULTS The levels of most glycolysis-related metabolites were not different between low-MTV and high-MTV tumors. The level of component of the initial part of the tricarboxylic acid (TCA) cycle, citrate, was significantly lower in the high-MTV tumor than in the low-MTV tumor. The TCA intermediate succinate level was significantly higher in the high-MTV tumor than in the low-MTV tumor. In contrast, the TCA intermediate fumarate level was significantly lower in the high-MTV tumor than in the low-MTV tumor. The levels of many amino acids were significantly higher in the high-MTV tumor than in the low-MTV tumor. CONCLUSIONS Although preliminary, these results suggest that tumors with high FDG metabolism in CRC may obtain more energy by using a reverse reaction of the TCA cycle and amino-acid metabolism. However, further research is required to clarify this relationship.
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Affiliation(s)
- Masashi Imajo
- Department of Radiology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-Cho, Kita-Gun, Kagawa, 761-0793, Japan
| | - Takashi Norikane
- Department of Radiology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-Cho, Kita-Gun, Kagawa, 761-0793, Japan
| | - Yuka Yamamoto
- Department of Radiology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-Cho, Kita-Gun, Kagawa, 761-0793, Japan.
| | - Yukito Maeda
- Department of Clinical Radiology, Kagawa University Hospital, Miki-Cho, Kagawa, Japan
| | - Kaori Saitoh
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata, Japan
| | - Keiko Kato
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata, Japan
| | - Tomoyoshi Soga
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata, Japan
| | - Keiichi Okano
- Department of Gastroenterological Surgery, Faculty of Medicine, Kagawa University, Miki-Cho, Kagawa, Japan
| | - Yoshihiro Nishiyama
- Department of Radiology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-Cho, Kita-Gun, Kagawa, 761-0793, Japan
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Baysal BE, Alahmari AA, Rodrick TC, Tabaczynski D, Curtin L, Seshadri M, Jones DR, Sexton S. Succinate dehydrogenase inversely regulates red cell distribution width and healthy lifespan in chronically hypoxic mice. JCI Insight 2022; 7:158737. [PMID: 35881479 PMCID: PMC9536274 DOI: 10.1172/jci.insight.158737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 07/21/2022] [Indexed: 11/17/2022] Open
Abstract
Increased red cell distribution width (RDW), which measures erythrocyte volume (MCV) variability (anisocytosis), has been linked to early mortality in many diseases and in older adults through unknown mechanisms. Hypoxic stress has been proposed as a potential mechanism. However, experimental models to investigate the link between increased RDW and reduced survival are lacking. Here, we show that lifelong hypobaric hypoxia (~10% O2) increases erythrocyte numbers, hemoglobin and RDW, while reducing longevity in male mice. Compound heterozygous knockout (chKO) mutations in succinate dehydrogenase (Sdh; mitochondrial complex II) genes Sdhb, Sdhc and Sdhd reduce Sdh subunit protein levels, RDW, and increase healthy lifespan compared to wild-type (WT) mice in chronic hypoxia. RDW-SD, a direct measure of MCV variability, and the standard deviation of MCV (1SD-RDW) show the most statistically significant reductions in Sdh hKO mice. Tissue metabolomic profiling of 147 common metabolites shows the largest increase in succinate with elevated succinate to fumarate and succinate to oxoglutarate (2-ketoglutarate) ratios in Sdh hKO mice. These results demonstrate that mitochondrial complex II level is an underlying determinant of both RDW and healthy lifespan in hypoxia, and suggest that therapeutic targeting of Sdh might reduce high RDW-associated clinical mortality in hypoxic diseases.
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Affiliation(s)
- Bora E Baysal
- Department of Pathology and Laboratory Medicine, Roswell Park Comprehensive Cancer Center, Buffalo, United States of America
| | - Abdulrahman A Alahmari
- Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, United States of America
| | - Tori C Rodrick
- Metabolomics Core Resource Laboratory, NYU Langone Health, New York, United States of America
| | - Debra Tabaczynski
- Department of Molecular & Cellular Biology, Roswell Park Comprehensive Cancer Center, Buffalo, United States of America
| | - Leslie Curtin
- Laboratory Animal Shared Resources, Roswell Park Comprehensive Cancer Center, Buffalo, United States of America
| | - Mukund Seshadri
- Department of Dentistry and Oral Oncology, Roswell Park Comprehensive Cancer Center, Buffalo, United States of America
| | - Drew R Jones
- Metabolomics Core Resource Laboratory, NYU Langone Health, New York, United States of America
| | - Sandra Sexton
- Laboratory Animal Shared Resources, Roswell Park Comprehensive Cancer Center, Buffalo, United States of America
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Lautens MJ, Tan JH, Serrat X, Del Borrello S, Schertzberg MR, Fraser AG. Identification of enzymes that have helminth-specific active sites and are required for Rhodoquinone-dependent metabolism as targets for new anthelmintics. PLoS Negl Trop Dis 2021; 15:e0009991. [PMID: 34843467 PMCID: PMC8659336 DOI: 10.1371/journal.pntd.0009991] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 12/09/2021] [Accepted: 11/11/2021] [Indexed: 11/18/2022] Open
Abstract
Soil transmitted helminths (STHs) are major human pathogens that infect over a billion people. Resistance to current anthelmintics is rising and new drugs are needed. Here we combine multiple approaches to find druggable targets in the anaerobic metabolic pathways STHs need to survive in their mammalian host. These require rhodoquinone (RQ), an electron carrier used by STHs and not their hosts. We identified 25 genes predicted to act in RQ-dependent metabolism including sensing hypoxia and RQ synthesis and found 9 are required. Since all 9 have mammalian orthologues, we used comparative genomics and structural modeling to identify those with active sites that differ between host and parasite. Together, we found 4 genes that are required for RQ-dependent metabolism and have different active sites. Finding these high confidence targets can open up in silico screens to identify species selective inhibitors of these enzymes as new anthelmintics.
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Affiliation(s)
- Margot J. Lautens
- The Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - June H. Tan
- The Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Xènia Serrat
- The Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | | | | | - Andrew G. Fraser
- The Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
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Foomani FH, Jarzembowski JA, Mostaghimi S, Mehrvar S, Kumar SN, Ranji M. Optical Metabolic Imaging of Mitochondrial Dysfunction on HADH Mutant Newborn Rat Hearts. IEEE JOURNAL OF TRANSLATIONAL ENGINEERING IN HEALTH AND MEDICINE 2021; 9:1800407. [PMID: 34462673 PMCID: PMC8396955 DOI: 10.1109/jtehm.2021.3104966] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/15/2021] [Accepted: 08/03/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND Mitochondrial [Formula: see text]-oxidation of fatty acids is the primary energy source for the heart and carried out by Hydroxy Acyl-CoA Dehydrogenase (HADH) encoded trifunctional protein. Mutations in the genes encoding mitochondrial proteins result in functionally defective protein complexes that contribute to energy deficiencies, excessive reactive oxygen species (ROS) production, and accumulation of damaged mitochondria. We hypothesize that a dramatic alternation in redox state and associated mitochondrial dysfunction is the underlying cause of Fatty Acid Oxidation (FAO) deficiency mutant, resulting in heart failure. Mitochondrial co-enzymes, NADH and FAD, are autofluorescent metabolic indices of cells when imaged, yield a quantitative assessment of the cells' redox status and, in turn, that of the tissue and organ. METHOD We utilized an optical cryo-imager to quantitively evaluate the three-dimensional distribution of mitochondrial redox state in newborn rats' hearts and kidneys. Redox ratio (RR) assessment shows that mitochondrial dysfunction is extreme and could contribute to severe heart problems and eventual heart failure in the mutants. RESULTS Three-dimensional redox ratio (NADH/FAD) rendering, and the volumetric mean value calculations confirmed significantly decreased cardiac RR in mutants by 31.90% and 12.32%, in renal mitochondrial RR compared to wild-type control. Further, histological assessment of newborn heart myocardial tissue indicated no significant difference in myocardial tissue architecture in both control and severe (HADHAe4-/-) conditions. CONCLUSION These results demonstrate that optical imaging can accurately estimate the redox state changes in newborn rat organs. It is also apparent that the FAO mutant's heart tissue with a low redox ratio is probably more vulnerable to cumulative damages than kidneys and fails prematurely, contributing to sudden death.
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Affiliation(s)
- Farnaz H. Foomani
- Biophotonics LaboratoryDepartment of Electrical EngineeringUniversity of Wisconsin–MilwaukeeMilwaukeeWI53201USA
| | - Jason A. Jarzembowski
- Department of Pathology and Laboratory MedicineMedical College of WisconsinMilwaukeeWI53226USA
| | - Soudeh Mostaghimi
- Biophotonics LaboratoryDepartment of Electrical EngineeringUniversity of Wisconsin–MilwaukeeMilwaukeeWI53201USA
| | - Shima Mehrvar
- Biophotonics LaboratoryDepartment of Electrical EngineeringUniversity of Wisconsin–MilwaukeeMilwaukeeWI53201USA
| | - Suresh N. Kumar
- Department of Pathology and Laboratory MedicineMedical College of WisconsinMilwaukeeWI53226USA
| | - Mahsa Ranji
- Biophotonics LaboratoryDepartment of Electrical Engineering and Computer Science (EECS)ISENSE Institute, Florida Atlantic UniversityBoca RatonFL33431USA
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Mitochondria as a potential target for the development of prophylactic and therapeutic drugs against Schistosoma mansoni infection. Antimicrob Agents Chemother 2021; 65:e0041821. [PMID: 34339272 DOI: 10.1128/aac.00418-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Emergence of parasites resistant to praziquantel, the only therapeutic agent, and its ineffectiveness as a prophylactic agent (inactive against the migratory/juvenile Schistosoma mansoni), makes the development of new antischistosomal drugs urgent. The parasite's mitochondrion is an attractive target for drug development because this organelle is essential for survival throughout the parasite's life cycle. We investigated the effects of 116 compounds against Schistosoma mansoni cercariae motility that have been reported to affect mitochondria-related processes in other organisms. Next, eight compounds plus two controls (mefloquine and praziquantel) were selected and assayed against motility of schistosomula (in vitro) and adults (ex vivo). Prophylactic and therapeutic assays were performed using infected mouse models. Inhibition of oxygen consumption rate (OCR) was assayed using Seahorse XFe24 Analyzer. All selected compounds showed excellent prophylactic activity, reducing the worm burden in the lungs to less than 15% that obtained in the vehicle control. Notably, ascofuranone showed the highest activity with a 98% reduction of the worm burden, suggesting the potential for development of ascofuranone as a prophylactic agent. The worm burden of infected mice with S. mansoni at the adult stage was reduced by more than 50% in mice treated with mefloquine, nitazoxanide, amiodarone, ascofuranone, pyrvinium pamoate, or plumbagin. Moreover, adult mitochondrial OCR was severely inhibited by ascofuranone, atovaquone, and nitazoxanide, while pyrvinium pamoate inhibited both mitochondrial and non-mitochondrial OCRs. These results demonstrate that the mitochondria of S. mansoni are feasible target for drug development.
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Antiparasitic Effects of Selected Isoflavones on Flatworms. Helminthologia 2021; 58:1-16. [PMID: 33664614 PMCID: PMC7912234 DOI: 10.2478/helm-2021-0004] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 12/07/2020] [Indexed: 01/13/2023] Open
Abstract
Medicinal plants have been successfully used in the ethno medicine for a wide range of diseases since ancient times. The research on natural products has allowed the discovery of biologically relevant compounds inspired by plant secondary metabolites, what contributed to the development of many chemotherapeutic drugs. Flavonoids represent a group of therapeutically very effective plant secondary metabolites and selected molecules were shown to exert also antiparasitic activity. This work summarizes the recent knowledge generated within past three decades about potential parasitocidal activities of several flavonoids with different chemical structures, particularly on medically important flatworms such as Schistosoma spp., Fasciola spp., Echinococcus spp., Raillietina spp., and model cestode Mesocestoides vogae. Here we focus on curcumin, genistein, quercetin and silymarin complex of flavonolignans. All of them possess a whole spectrum of biological activities on eukaryotic cells which have multi-therapeutic effects in various diseases. In vitro they can induce profound alterations in the tegumental architecture and its functions as well as their activity can significantly modulate or damage worm´s metabolism directly by interaction with enzymes or signaling molecules in dose-dependent manner. Moreover, they seem to differentially regulate the RNA activity in numbers of worm´s genes. This review suggests that examined flavonoids and their derivates are promising molecules for antiparasitic drug research. Due to lack of toxicity, isoflavons could be used directly for therapy, or as adjuvant therapy for diseases caused by medically important cestodes and trematodes.
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Preza M, Calvelo J, Langleib M, Hoffmann F, Castillo E, Koziol U, Iriarte A. Stage-specific transcriptomic analysis of the model cestode Hymenolepis microstoma. Genomics 2021; 113:620-632. [PMID: 33485950 DOI: 10.1016/j.ygeno.2021.01.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 12/20/2020] [Accepted: 01/17/2021] [Indexed: 12/11/2022]
Abstract
Most parasitic flatworms go through different life stages with important physiological and morphological changes. In this work, we used a transcriptomic approach to analyze the main life-stages of the model tapeworm Hymenolepis microstoma (eggs, cysticercoids, and adults). Our results showed massive transcriptomic changes in this life cycle, including key gene families that contribute substantially to the expression load in each stage. In particular, different members of the cestode-specific hydrophobic ligand-binding protein (HLBP) family are among the most highly expressed genes in each life stage. We also found the transcriptomic signature of major metabolic changes during the transition from cysticercoids to adult worms. Thus, this work contributes to uncovering the gene expression changes that accompany the development of this important cestode model species, and to the best of our knowledge represents the first transcriptomic study with robust replicates spanning all of the main life stages of a tapeworm.
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Affiliation(s)
- Matías Preza
- Sección Biología Celular, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
| | - Javier Calvelo
- Sección Biología Celular, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay; Laboratorio Biología Computacional, Departamento de Desarrollo Biotecnológico, Instituto de Higiene, Facultad de Medicina, Universidad de la República, Montevideo 11600, Uruguay
| | - Mauricio Langleib
- Laboratorio Biología Computacional, Departamento de Desarrollo Biotecnológico, Instituto de Higiene, Facultad de Medicina, Universidad de la República, Montevideo 11600, Uruguay
| | - Federico Hoffmann
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, MS 39762, United States
| | - Estela Castillo
- Sección Bioquímica, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
| | - Uriel Koziol
- Sección Biología Celular, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay.
| | - Andrés Iriarte
- Laboratorio Biología Computacional, Departamento de Desarrollo Biotecnológico, Instituto de Higiene, Facultad de Medicina, Universidad de la República, Montevideo 11600, Uruguay.
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Preston S, Garcia-Bustos J, Hall LG, Martin SD, Le TG, Kundu A, Ghoshal A, Nguyen NH, Jiao Y, Ruan B, Xue L, Huang F, Chang BCH, McGee SL, Wells TNC, Palmer MJ, Jabbar A, Gasser RB, Baell JB. 1-Methyl-1 H-pyrazole-5-carboxamide Derivatives Exhibit Unexpected Acute Mammalian Toxicity. J Med Chem 2020; 64:840-844. [PMID: 33352050 DOI: 10.1021/acs.jmedchem.0c01793] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A series of 1-methyl-1H-pyrazole-5-carboxamides were synthesized as potent inhibitors of the parasitic nematode of sheep, Haemonchus contortus. These compounds did not show overt cytotoxicity to a range of mammalian cell lines under standard in vitro culture conditions, had high selectivity indices, and were progressed to an acute toxicity study in a rodent model. Strikingly, acute toxicity was observed in mice. Experiments measuring cellular respiration showed a dose-dependent inhibition of mitochondrial respiration. Under these conditions, potent cytotoxicity was observed for these compounds in rat hepatocytes suggesting that the potent acute mammalian toxicity of this chemotype is most likely associated with respiratory inhibition. In contrast, parasite toxicity was not correlated to acute toxicity or cytotoxicity in respiring cells. This paper highlights the importance of identifying an appropriate in vitro predictor of in vivo toxicity early on in the drug discovery pipeline, in particular assessment for in vitro mitochondrial toxicity.
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Affiliation(s)
- Sarah Preston
- School of Health and Life Sciences, Federation University, Ballarat, Victoria 3353, Australia
| | - Jose Garcia-Bustos
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Liam G Hall
- Metabolic Research Unit, Metabolic Reprogramming Laboratory, School of Medicine, Faculty of Health, Deakin University, Waurn Ponds, Victoria 3216, Australia
| | - Sheree D Martin
- Metabolic Research Unit, Metabolic Reprogramming Laboratory, School of Medicine, Faculty of Health, Deakin University, Waurn Ponds, Victoria 3216, Australia
| | - Thuy G Le
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Abhijit Kundu
- TCG Lifesciences Private Limited, Block BN, Plot 7, Salt-lake Electronics Complex, Sector V, Kolkata 700091, West Bengal, India
| | - Atanu Ghoshal
- TCG Lifesciences Private Limited, Block BN, Plot 7, Salt-lake Electronics Complex, Sector V, Kolkata 700091, West Bengal, India
| | - Nghi H Nguyen
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Yaqing Jiao
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Banfeng Ruan
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Lian Xue
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Fei Huang
- School of Pharmaceutical Sciences, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing 211816, People's Republic of China
| | | | - Sean L McGee
- Metabolic Research Unit, Metabolic Reprogramming Laboratory, School of Medicine, Faculty of Health, Deakin University, Waurn Ponds, Victoria 3216, Australia
| | | | | | - Abdul Jabbar
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Robin B Gasser
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Jonathan B Baell
- School of Pharmaceutical Sciences, Nanjing Tech University, No. 30 South Puzhu Road, Nanjing 211816, People's Republic of China.,Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
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Mochizuki K, Inaoka DK, Mazet M, Shiba T, Fukuda K, Kurasawa H, Millerioux Y, Boshart M, Balogun EO, Harada S, Hirayama K, Bringaud F, Kita K. The ASCT/SCS cycle fuels mitochondrial ATP and acetate production in Trypanosoma brucei. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148283. [PMID: 32763239 PMCID: PMC7402102 DOI: 10.1016/j.bbabio.2020.148283] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/22/2020] [Accepted: 07/29/2020] [Indexed: 11/03/2022]
Abstract
Acetate:succinate CoA transferase (ASCT) is a mitochondrial enzyme that catalyzes the production of acetate and succinyl-CoA, which is coupled to ATP production with succinyl-CoA synthetase (SCS) in a process called the ASCT/SCS cycle. This cycle has been studied in Trypanosoma brucei (T. brucei), a pathogen of African sleeping sickness, and is involved in (i) ATP and (ii) acetate production and proceeds independent of oxygen and an electrochemical gradient. Interestingly, knockout of ASCT in procyclic form (PCF) of T. brucei cause oligomycin A-hypersensitivity phenotype indicating that ASCT/SCS cycle complements the deficiency of ATP synthase activity. In bloodstream form (BSF) of T. brucei, ATP synthase works in reverse to maintain the electrochemical gradient by hydrolyzing ATP. However, no information has been available on the source of ATP, although ASCT/SCS cycle could be a potential candidate. Regarding mitochondrial acetate production, which is essential for fatty acid biosynthesis and growth of T. brucei, ASCT or acetyl-CoA hydrolase (ACH) are known to be its source. Despite the importance of this cycle, direct evidence of its function is lacking, and there are no comprehensive biochemical or structural biology studies reported so far. Here, we show that in vitro–reconstituted ASCT/SCS cycle is highly specific towards acetyl-CoA and has a higher kcat than that of yeast and bacterial ATP synthases. Our results provide the first biochemical basis for (i) rescue of ATP synthase-deficient phenotype by ASCT/SCS cycle in PCF and (ii) a potential source of ATP for the reverse reaction of ATP synthase in BSF. First biochemical and structural characterization of mitochondrial ASCT/SCS cycle It is essential for mitochondrial acetate/ATP production and T. brucei BSF growth. TbASCT/SCS cycle shows higher kcat than that of yeast and bacterial ATP synthases. Detailed comparative biochemical analysis between ASCT and human SCOT Active site residue and X-CoA binding site determined by site-directed mutagenesis
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Affiliation(s)
- Kota Mochizuki
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Japan; Graduate School of Biomedical Sciences, Nagasaki University, Japan
| | - Daniel Ken Inaoka
- Department of Molecular Infection Dynamics, Shionogi Global Infectious Diseases Division, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Japan; School of Tropical Medicine and Global Health, Nagasaki University, Japan; Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Japan.
| | - Muriel Mazet
- Laboratoire de Microbiologie Fondamentale et Pathogénicité (MFP), Université de Bordeaux, CNRS UMR-5234, France
| | - Tomoo Shiba
- Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Japan.
| | - Keisuke Fukuda
- Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Japan
| | - Hana Kurasawa
- Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Japan
| | - Yoann Millerioux
- Laboratoire de Microbiologie Fondamentale et Pathogénicité (MFP), Université de Bordeaux, CNRS UMR-5234, France
| | - Michael Boshart
- Fakultät für Biologie, Genetik, Ludwig-Maximilians-Universität München, Germany
| | - Emmanuel O Balogun
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Japan; Department of Biochemistry, Ahmadu Bello University, Nigeria
| | - Shigeharu Harada
- Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Japan
| | - Kenji Hirayama
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Japan
| | - Frédéric Bringaud
- Laboratoire de Microbiologie Fondamentale et Pathogénicité (MFP), Université de Bordeaux, CNRS UMR-5234, France
| | - Kiyoshi Kita
- School of Tropical Medicine and Global Health, Nagasaki University, Japan; Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Japan; Department of Host - Defense Biochemistry, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Japan
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11
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Zhang D, Zou H, Wu SG, Li M, Jakovlić I, Zhang J, Chen R, Li WX, Wang GT. Evidence for Adaptive Selection in the Mitogenome of a Mesoparasitic Monogenean Flatworm Enterogyrus malmbergi. Genes (Basel) 2019; 10:genes10110863. [PMID: 31671638 PMCID: PMC6896049 DOI: 10.3390/genes10110863] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/26/2019] [Accepted: 10/29/2019] [Indexed: 02/06/2023] Open
Abstract
Whereas a majority of monogenean flatworms are ectoparasitic, i.e., parasitize on external surfaces (mainly gills) of their fish hosts, Enterogyrus species (subfamily Ancyrocephalinae) are mesoparasitic, i.e., parasitize in the stomach of the host. As there are numerous drastic differences between these two environments (including lower oxygen availability), we hypothesized that this life-history innovation might have produced adaptive pressures on the energy metabolism, which is partially encoded by the mitochondrial genome (OXPHOS). To test this hypothesis, we sequenced mitochondrial genomes of two Ancyrocephalinae species: mesoparasitic E. malmbergi and ectoparasitic Ancyrocephalus mogurndae. The mitogenomic architecture of E. malmbergi is mostly standard for monogeneans, but that of A. mogurndae exhibits some unique features: missing trnL2 gene, very low AT content (60%), a non-canonical start codon of the nad2 gene, and exceptionally long tandem-repeats in the non-coding region (253 bp). Phylogenetic analyses produced paraphyletic Ancyrocephalinae (with embedded Dactylogyrinae), but with low support values. Selective pressure (PAML and HYPHY) and protein structure analyses all found evidence for adaptive evolution in cox2 and cox3 genes of the mesoparasitic E. malmbergi. These findings tentatively support our hypothesis of adaptive evolution driven by life-history innovations in the mitogenome of this species. However, as only one stomach-inhabiting mesoparasitic monogenean was available for this analysis, our findings should be corroborated on a larger number of mesoparasitic monogeneans and by physiological studies.
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Affiliation(s)
- Dong Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- University of Chinese Academy of Sciences, Beijing 100000, China.
| | - Hong Zou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
| | - Shan G Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- University of Chinese Academy of Sciences, Beijing 100000, China.
| | - Ming Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- University of Chinese Academy of Sciences, Beijing 100000, China.
| | | | - Jin Zhang
- Bio-Transduction Lab, Wuhan 430075, China.
| | - Rong Chen
- Bio-Transduction Lab, Wuhan 430075, China.
| | - Wen X Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- University of Chinese Academy of Sciences, Beijing 100000, China.
| | - Gui T Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
- University of Chinese Academy of Sciences, Beijing 100000, China.
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12
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Yanase S, Ishii T, Yasuda K, Ishii N. Metabolic Biomarkers in Nematode C. elegans During Aging. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1134:163-175. [PMID: 30919337 DOI: 10.1007/978-3-030-12668-1_9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Changes in energy metabolism occur not only in diseases such as cancer but also in the normal development and aging processes of various organisms. These metabolic changes result to lead to imbalances in energy metabolism related to cellular and tissue homeostasis. In the model organism C. elegans, which is used to study aging, an imbalance in age-related energy metabolism exists between mitochondrial oxidative phosphorylation and aerobic glycolysis. Cellular lactate and pyruvate are key intermediates in intracellular energy metabolic pathways and can indicate age-related imbalances in energy metabolism. Thus, the cellular lactate/pyruvate ratio can be monitored as a biomarker during aging. Moreover, recent studies have proposed a candidate novel biomarker for aging and age-related declines in the nematode C. elegans.
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Affiliation(s)
- Sumino Yanase
- Department of Health Science, Daito Bunka University School of Sports & Health Science, Higashi-matsuyama, Saitama, Japan. .,Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa, Japan.
| | - Takamasa Ishii
- Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Kayo Yasuda
- Department of Health Management, Undergraduate School of Health Studies, Tokai University, Hiratsuka, Kanagawa, Japan
| | - Naoaki Ishii
- Department of Health Management, Undergraduate School of Health Studies, Tokai University, Hiratsuka, Kanagawa, Japan
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Liu WC, Ren YX, Hao AY, Yu S, Shi X, Zhang XQ, Xing Y, Xiu ZL, Cui Y, Dong YS. The activities of wortmannilactones against helminth electron transport chain enzymes, structure-activity relationships, and the effect on Trichinella spiralis infected mice. J Antibiot (Tokyo) 2018; 71:731-740. [DOI: 10.1038/s41429-018-0061-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 03/13/2018] [Accepted: 04/02/2018] [Indexed: 11/09/2022]
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Schito L, Rey S. Cell-Autonomous Metabolic Reprogramming in Hypoxia. Trends Cell Biol 2017; 28:128-142. [PMID: 29191366 DOI: 10.1016/j.tcb.2017.10.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 10/25/2017] [Accepted: 10/25/2017] [Indexed: 12/31/2022]
Abstract
Molecular oxygen (O2) is a universal electron acceptor that enables ATP synthesis through mitochondrial respiration in all metazoans. Consequently, hypoxia (low O2) has arisen as an organizing principle for cellular evolution, metabolism, and (patho)biology, eliciting a remarkable panoply of metabolic adaptations that trigger transcriptional, translational, post-translational, and epigenetic responses to determine cellular fitness. In this review we summarize current and emerging cell-autonomous molecular mechanisms that induce hypoxic metabolic reprogramming in health and disease.
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Affiliation(s)
- Luana Schito
- Biological Sciences, Sunnybrook Research Institute, Toronto, ON M4N 3M5, Canada.
| | - Sergio Rey
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada.
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Zimorski V, Rauch C, van Hellemond JJ, Tielens AGM, Martin WF. The Mitochondrion of Euglena gracilis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 979:19-37. [PMID: 28429315 DOI: 10.1007/978-3-319-54910-1_2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In the presence of oxygen, Euglena gracilis mitochondria function much like mammalian mitochondria. Under anaerobiosis, E. gracilis mitochondria perform a malonyl-CoA independent synthesis of fatty acids leading to accumulation of wax esters, which serve as the sink for electrons stemming from glycolytic ATP synthesis and pyruvate oxidation. Some components (enzymes and cofactors) of Euglena's anaerobic energy metabolism are found among the anaerobic mitochondria of invertebrates, others are found among hydrogenosomes, the H2-producing anaerobic mitochondria of protists.
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Affiliation(s)
- Verena Zimorski
- Institute of Molecular Evolution, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Cessa Rauch
- Institute of Molecular Evolution, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Jaap J van Hellemond
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Aloysius G M Tielens
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands.,Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - William F Martin
- Institute of Molecular Evolution, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany.
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Zieliński ŁP, Smith AC, Smith AG, Robinson AJ. Metabolic flexibility of mitochondrial respiratory chain disorders predicted by computer modelling. Mitochondrion 2016; 31:45-55. [PMID: 27697518 PMCID: PMC5115619 DOI: 10.1016/j.mito.2016.09.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 05/30/2016] [Accepted: 09/29/2016] [Indexed: 11/28/2022]
Abstract
Mitochondrial respiratory chain dysfunction causes a variety of life-threatening diseases affecting about 1 in 4300 adults. These diseases are genetically heterogeneous, but have the same outcome; reduced activity of mitochondrial respiratory chain complexes causing decreased ATP production and potentially toxic accumulation of metabolites. Severity and tissue specificity of these effects varies between patients by unknown mechanisms and treatment options are limited. So far most research has focused on the complexes themselves, and the impact on overall cellular metabolism is largely unclear. To illustrate how computer modelling can be used to better understand the potential impact of these disorders and inspire new research directions and treatments, we simulated them using a computer model of human cardiomyocyte mitochondrial metabolism containing over 300 characterised reactions and transport steps with experimental parameters taken from the literature. Overall, simulations were consistent with patient symptoms, supporting their biological and medical significance. These simulations predicted: complex I deficiencies could be compensated using multiple pathways; complex II deficiencies had less metabolic flexibility due to impacting both the TCA cycle and the respiratory chain; and complex III and IV deficiencies caused greatest decreases in ATP production with metabolic consequences that parallel hypoxia. Our study demonstrates how results from computer models can be compared to a clinical phenotype and used as a tool for hypothesis generation for subsequent experimental testing. These simulations can enhance understanding of dysfunctional mitochondrial metabolism and suggest new avenues for research into treatment of mitochondrial disease and other areas of mitochondrial dysfunction.
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Affiliation(s)
- Łukasz P Zieliński
- MRC Mitochondrial Biology Unit, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY, UK; University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0SP, UK
| | - Anthony C Smith
- MRC Mitochondrial Biology Unit, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY, UK
| | - Alexander G Smith
- MRC Mitochondrial Biology Unit, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY, UK
| | - Alan J Robinson
- MRC Mitochondrial Biology Unit, Cambridge Biomedical Campus, Hills Road, Cambridge, CB2 0XY, UK.
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17
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Nakano T, Takahashi-Nakaguchi A, Yamamoto M, Watanabe M. Pierisins and CARP-1: ADP-ribosylation of DNA by ARTCs in butterflies and shellfish. Curr Top Microbiol Immunol 2015; 384:127-49. [PMID: 25033755 DOI: 10.1007/82_2014_416] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The cabbage butterfly, Pieris rapae, and related species possess a previously unknown ADP-ribosylating toxin, guanine specific ADP-ribosyltransferase. This enzyme toxin, known as pierisin, consists of enzymatic N-terminal domain and receptor-binding C-terminal domain, or typical AB-toxin structure. Pierisin efficiently transfers an ADP-ribosyl moiety to the N(2) position of the guanine base of dsDNA. Receptors for pierisin are suggested to be the neutral glycosphingolipids, globotriaosylceramide (Gb3), and globotetraosylceramide (Gb4). This DNA-modifying toxin exhibits strong cytotoxicity and induces apoptosis in various human cell lines, which can be blocked by Bcl-2. Pierisin also produces detrimental effects on the eggs and larvae of the non-habitual parasitoids. In contrast, a natural parasitoid of the cabbage butterfly, Cotesia glomerata, was resistant to this toxin. The physiological role of pierisin in the butterfly is suggested to be a defense factor against parasitization by wasps. Other type of DNA ADP-ribosyltransferase is present in certain kinds of edible clams. For example, the CARP-1 protein found in Meretrix lamarckii consists of an enzymatic domain without a possible receptor-binding domain. Pierisin and CARP-1 are almost fully non-homologous at the amino acid sequence level, but other ADP-ribosyltransferases homologous to pierisin are present in different biological species such as eubacterium Streptomyces. Possible diverse physiological roles of the DNA ADP-ribosyltransferases are discussed.
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Affiliation(s)
- Tsuyoshi Nakano
- Division of Cancer Development System, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan,
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Ogawa T, Washio J, Takahashi T, Echigo S, Takahashi N. Glucose and glutamine metabolism in oral squamous cell carcinoma: insight from a quantitative metabolomic approach. Oral Surg Oral Med Oral Pathol Oral Radiol 2014; 118:218-25. [PMID: 24927638 DOI: 10.1016/j.oooo.2014.04.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 03/31/2014] [Accepted: 04/07/2014] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To characterize the metabolic system of oral squamous cell carcinoma (OSCC) by metabolome analysis. STUDY DESIGN The metabolome profiles, including the Embden-Meyerhof-Parnas pathway (EMPP), the pentose phosphate pathway, the tricarboxylic acid cycle (TCAC), and amino acids, were obtained from OSCC and its surrounding normal tissues (32 patients) using capillary electrophoresis and a time-of-flight mass spectrometer. RESULTS Enhancement of glucose consumption and lactate production (Warburg effect) was observed in OSCC tissues. The decrease of glucose along with the decrease of the downstream intermediates in the EMPP suggests that incorporated glucose is mainly consumed for biosynthesis. Glutamine consumption with the increase of the intermediates in the last half of the TCAC suggests the involvement of glutaminolysis, in which glutamine is converted to lactate via the last half of the TCAC. CONCLUSIONS It is suggested that OSCC tissues show the Warburg effect, which stems from the combined enhancement of glucose consumption and glutaminolysis.
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Affiliation(s)
- Tamaki Ogawa
- Division of Oral Ecology and Biochemistry, Department of Oral Biology, Tohoku University Graduate School of Dentistry, Sendai, Japan; Division of Oral and Maxillofacial Surgery, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Jumpei Washio
- Division of Oral Ecology and Biochemistry, Department of Oral Biology, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Tetsu Takahashi
- Division of Oral and Maxillofacial Surgery, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Seishi Echigo
- Division of Oral and Maxillofacial Surgery, Tohoku University Graduate School of Dentistry, Sendai, Japan
| | - Nobuhiro Takahashi
- Division of Oral and Maxillofacial Surgery, Tohoku University Graduate School of Dentistry, Sendai, Japan.
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Targeting the mitochondrial electron transport chain of Plasmodium falciparum: new strategies towards the development of improved antimalarials for the elimination era. Future Med Chem 2014; 5:1573-91. [PMID: 24024949 DOI: 10.4155/fmc.13.121] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Despite intense efforts, there has not been a truly new antimalarial, possessing a novel mechanism of action, registered for over 10 years. By virtue of a novel mode of action, it is hoped that the global challenge of multidrug-resistant parasites can be overcome, as well as developing drugs that possess prophylaxis and/or transmission-blocking properties, towards an elimination agenda. Many target-based and whole-cell screening drug development programs have been undertaken in recent years and here an overview of specific projects that have focused on targeting the parasite's mitochondrial electron transport chain is presented. Medicinal chemistry activity has largely focused on inhibitors of the parasite cytochrome bc1 Complex (Complex III) including acridinediones, pyridones and quinolone aryl esters, as well as inhibitors of dihydroorotate dehydrogenase that includes triazolopyrimidines and benzimidazoles. Common barriers to progress and opportunities for novel chemistry and potential additional electron transport chain targets are discussed in the context of the target candidate profiles for uncomplicated malaria.
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Takahashi E, Sato M. Anaerobic respiration sustains mitochondrial membrane potential in a prolyl hydroxylase pathway-activated cancer cell line in a hypoxic microenvironment. Am J Physiol Cell Physiol 2013; 306:C334-42. [PMID: 24048731 DOI: 10.1152/ajpcell.00255.2013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
To elucidate how tumor cells produce energy in oxygen-depleted microenvironments, we studied the possibility of mitochondrial electron transport without oxygen. We produced well-controlled oxygen gradients (ΔO2) in monolayer-cultured cells. We then visualized oxygen levels and mitochondrial membrane potential (ΔΦm) in individual cells by using the red shift of green fluorescent protein (GFP) fluorescence and a cationic fluorescent dye, respectively. In this two-dimensional tissue model, ΔΦm was abolished in cells >500 μm from the oxygen source [the anoxic front (AF)], indicating limitations in diffusional oxygen delivery. This result perfectly matched GFP-determined ΔO2. In cells pretreated with dimethyloxaloylglycine (DMOG), a prolyl hydroxylase domain-containing protein (PHD) inhibitor, the AF was expanded to 1,500-2,000 μm from the source. In these cells, tissue ΔO2 was substantially decreased, indicating that PHD pathway activation suppressed mitochondrial respiration. The expansion of the AF and the reduction of ΔO2 were much more prominent in a cancer cell line (Hep3B) than in the equivalent fibroblast-like cell line (COS-7). Hence, the results indicate that PHD pathway-activated cells can sustain ΔΦm, despite significantly decreased electron flux to complex IV. Complex II inhibition abolished the effect of DMOG in expanding the AF, although tissue ΔO2 remained shallow. Separate experiments demonstrated that complex II plays a substantial role in sustaining ΔΦm in DMOG-pretreated Hep3B cells with complex III inhibition. From these results, we conclude that PHD pathway activation can sustain ΔΦm in an otherwise anoxic microenvironment by decreasing tissue ΔO2 while activating oxygen-independent electron transport in mitochondria.
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Affiliation(s)
- Eiji Takahashi
- Advanced Technology Fusion, Graduate School of Science and Engineering, Saga University, Saga, Japan; and
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Baysal BE, De Jong K, Liu B, Wang J, Patnaik SK, Wallace PK, Taggart RT. Hypoxia-inducible C-to-U coding RNA editing downregulates SDHB in monocytes. PeerJ 2013; 1:e152. [PMID: 24058882 PMCID: PMC3775634 DOI: 10.7717/peerj.152] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 08/14/2013] [Indexed: 12/30/2022] Open
Abstract
Background. RNA editing is a post-transcriptional regulatory mechanism that can alter the coding sequences of certain genes in response to physiological demands. We previously identified C-to-U RNA editing (C136U, R46X) which inactivates a small fraction of succinate dehydrogenase (SDH; mitochondrial complex II) subunit B gene (SDHB) mRNAs in normal steady-state peripheral blood mononuclear cells (PBMCs). SDH is a heterotetrameric tumor suppressor complex which when mutated causes paraganglioma tumors that are characterized by constitutive activation of hypoxia inducible pathways. Here, we studied regulation, extent and cell type origin of SDHB RNA editing. Methods. We used short-term cultured PBMCs obtained from random healthy platelet donors, performed monocyte enrichment by cold aggregation, employed a novel allele-specific quantitative PCR method, flow cytometry, immunologic cell separation, gene expression microarray, database analysis and high-throughput RNA sequencing. Results. While the editing rate is low in uncultured monocyte-enriched PBMCs (average rate 2.0%, range 0.4%-6.3%, n = 42), it is markedly upregulated upon exposure to 1% oxygen tension (average rate 18.2%, range 2.8%-49.4%, n = 14) and during normoxic macrophage differentiation in the presence of serum (average rate 10.1%, range 2.7%-18.8%, n = 17). The normoxic induction of SDHB RNA editing was associated with the development of dense adherent aggregates of monocytes in culture. CD14-positive monocyte isolation increased the percentages of C136U transcripts by 1.25-fold in normoxic cultures (n = 5) and 1.68-fold in hypoxic cultures (n = 4). CD14-negative lymphocytes showed no evidence of SDHB editing. The SDHB genomic DNA remained wild-type during increased RNA editing. Microarray analysis showed expression changes in wound healing and immune response pathway genes as the editing rate increased in normoxic cultures. High-throughput sequencing of SDHB and SDHD transcripts confirmed the induction of C136U RNA editing in normoxic cultures but showed no additional verifiable coding edits. Analysis of SDHB RNA sequence data from 16 normal human tissues from the Illumina Body Map and from 45 samples representing 23 different cell types from the ENCODE projects confirmed the occurrence of site-specific C136U editing in whole blood (1.7%) and two primary CD14+ monocyte samples (1.9% and 2.6%). In contrast, the other cell types showed an average of 0.2% and 0.1% C136U editing rates in the two databases, respectively. Conclusions. These findings demonstrate that C-to-U coding RNA editing of certain genes is dynamically induced by physiologically relevant environmental factors and suggest that epigenetic downregulation of SDHB by site-specific RNA editing plays a role in hypoxia adaptation in monocytes.
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Affiliation(s)
- Bora E Baysal
- Departments of Pathology and Laboratory Medicine, Roswell Park Cancer Institute , Buffalo, NY , USA
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Olszewska A, Szewczyk A. Mitochondria as a pharmacological target: magnum overview. IUBMB Life 2013; 65:273-81. [PMID: 23441041 DOI: 10.1002/iub.1147] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Accepted: 12/14/2012] [Indexed: 12/30/2022]
Abstract
Mitochondria, responsible for energy metabolism within the cell, act as signaling organelles. Mitochondrial dysfunction may lead to cell death and oxidative stress and may disturb calcium metabolism. Additionally, mitochondria play a pivotal role in cardioprotective phenomena and a variety of neurodegenerative disorders ranging from Parkinson's to Alzheimer's disease. Mitochondrial DNA mutations may lead to impaired respiration. Hence, targeting the mitochondria with drugs offers great potential for new therapeutic approaches. The purpose of this overview is to present the recent state of knowledge concerning the interactions of various substances with mitochondria.
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Affiliation(s)
- Anna Olszewska
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Warsaw, Poland.
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Jiang C, Liu Y, Meng C, Wu L, Huang J, Deng J, Wang J, Shen P, Wu B. Expression of a metagenome-derived fumarate reductase from marine microorganisms and its characterization. Folia Microbiol (Praha) 2013; 58:663-71. [DOI: 10.1007/s12223-013-0256-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 04/23/2013] [Indexed: 12/21/2022]
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Cloning and characterization of hypoxia-inducible factor-1 subunits from Ascaris suum — A parasitic nematode highly adapted to changes of oxygen conditions during its life cycle. Gene 2013; 516:39-47. [DOI: 10.1016/j.gene.2012.12.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 11/30/2012] [Accepted: 12/03/2012] [Indexed: 12/23/2022]
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Harada S, Inaoka DK, Ohmori J, Kita K. Diversity of parasite complex II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:658-67. [PMID: 23333273 DOI: 10.1016/j.bbabio.2013.01.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 01/07/2013] [Accepted: 01/09/2013] [Indexed: 10/27/2022]
Abstract
Parasites have developed a variety of physiological functions necessary for completing at least part of their life cycles in the specialized environments of surrounding the parasites in the host. Regarding energy metabolism, which is essential for survival, parasites adapt to the low oxygen environment in mammalian hosts by using metabolic systems that are very different from those of the hosts. In many cases, the parasite employs aerobic metabolism during the free-living stage outside the host but undergoes major changes in developmental control and environmental adaptation to switch to anaerobic energy metabolism. Parasite mitochondria play diverse roles in their energy metabolism, and in recent studies of the parasitic nematode, Ascaris suum, the mitochondrial complex II plays an important role in anaerobic energy metabolism of parasites inhabiting hosts by acting as a quinol-fumarate reductase. In Trypanosomes, parasite complex II has been found to have a novel function and structure. Complex II of Trypanosoma cruzi is an unusual supramolecular complex with a heterodimeric iron-sulfur subunit and seven additional non-catalytic subunits. The enzyme shows reduced binding affinities for both substrates and inhibitors. Interestingly, this structural organization is conserved in all trypanosomatids. Since the properties of complex II differ across a wide range of parasites, this complex is a potential target for the development of new chemotherapeutic agents. In this regard, structural information on the target enzyme is essential for the molecular design of drugs. This article is part of a Special Issue entitled: Respiratory complex II: Role in cellular physiology and disease.
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Affiliation(s)
- Shigeharu Harada
- Department of Applied Biology, Kyoto Institute of Technology, Kyoto, Japan.
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Baysal BE. Mitochondrial complex II and genomic imprinting in inheritance of paraganglioma tumors. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:573-7. [PMID: 23291190 DOI: 10.1016/j.bbabio.2012.12.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 12/17/2012] [Accepted: 12/19/2012] [Indexed: 11/18/2022]
Abstract
Germ line heterozygous mutations in the structural subunit genes of mitochondrial complex II (succinate dehydrogenase; SDH) and the regulatory gene SDHAF2 predispose to paraganglioma tumors which show constitutive activation of hypoxia inducible pathways. Mutations in SDHD and SDHAF2 cause highly penetrant multifocal tumor development after a paternal transmission, whereas maternal transmission rarely, if ever, leads to tumor development. This transmission pattern is consistent with genomic imprinting. Recent molecular evidence supports a model for tissue-specific imprinted regulation of the SDHD gene by a long range epigenetic mechanism. In addition, there is evidence of SDHB mRNA editing in peripheral blood mononuclear cells and long-term balancing selection operating on the SDHA gene. Regulation of SDH subunit expression by diverse epigenetic mechanisms implicates a crucial dosage-dependent role for SDH in oxygen homeostasis. This article is part of a Special Issue entitled: Respiratory complex II: Role in cellular physiology and disease.
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Affiliation(s)
- Bora E Baysal
- Department of Pathology, Roswell Park Cancer Institute, Buffalo, NY, USA.
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Lorsuwannarat N, Saowakon N, Ramasoota P, Wanichanon C, Sobhon P. The anthelmintic effect of plumbagin on Schistosoma mansoni. Exp Parasitol 2013; 133:18-27. [DOI: 10.1016/j.exppara.2012.10.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Revised: 09/28/2012] [Accepted: 10/02/2012] [Indexed: 11/29/2022]
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Osaki T, Azuma K, Kurozumi S, Takamori Y, Tsuka T, Imagawa T, Okamoto Y, Minami S. Metabolomic analyses of blood plasma after oral administration of D-glucosamine hydrochloride to dogs. Mar Drugs 2012; 10:1873-1882. [PMID: 23015778 PMCID: PMC3447342 DOI: 10.3390/md10081873] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 07/02/2012] [Accepted: 08/15/2012] [Indexed: 11/16/2022] Open
Abstract
D-Glucosamine hydrochloride (GlcN∙HCl) is an endogenous amino monosaccharide synthesized from glucose that is useful in the treatment of joint diseases in both humans and animals. The aim of this study was to examine amino acid metabolism in dogs after oral administration of GlcN∙HCl. Accelerated fumarate respiration and elevated plasma levels of lactic acid and alanine were observed after administration. These results suggest that oral administration of GlcN∙HCl induces anaerobic respiration and starvation in cells, and we hypothesize that these conditions promote cartilage regeneration. Further studies are required to evaluate the expression of transforming growth factor-beta (TGF-β).
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Affiliation(s)
- Tomohiro Osaki
- Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Tottori University, 4-101 Koyama-minami, Tottori 680-8553, Japan; (K.A.); (T.T.); (T.I.); (Y.O.); (S.M.)
- Author to whom correspondence should be addressed; ; Tel./Fax: +81-857-31-5434
| | - Kazuo Azuma
- Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Tottori University, 4-101 Koyama-minami, Tottori 680-8553, Japan; (K.A.); (T.T.); (T.I.); (Y.O.); (S.M.)
| | - Seiji Kurozumi
- Koyo Chemical Co. Ltd., 3-11-15 Iidabashi, Chiyodaku, Tokyo 102-0072, Japan; (S.K.); (Y.T.)
| | - Yoshimori Takamori
- Koyo Chemical Co. Ltd., 3-11-15 Iidabashi, Chiyodaku, Tokyo 102-0072, Japan; (S.K.); (Y.T.)
| | - Takeshi Tsuka
- Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Tottori University, 4-101 Koyama-minami, Tottori 680-8553, Japan; (K.A.); (T.T.); (T.I.); (Y.O.); (S.M.)
| | - Tomohiro Imagawa
- Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Tottori University, 4-101 Koyama-minami, Tottori 680-8553, Japan; (K.A.); (T.T.); (T.I.); (Y.O.); (S.M.)
| | - Yoshiharu Okamoto
- Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Tottori University, 4-101 Koyama-minami, Tottori 680-8553, Japan; (K.A.); (T.T.); (T.I.); (Y.O.); (S.M.)
| | - Saburo Minami
- Department of Veterinary Clinical Medicine, School of Veterinary Medicine, Tottori University, 4-101 Koyama-minami, Tottori 680-8553, Japan; (K.A.); (T.T.); (T.I.); (Y.O.); (S.M.)
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Sakai C, Tomitsuka E, Esumi H, Harada S, Kita K. Mitochondrial fumarate reductase as a target of chemotherapy: From parasites to cancer cells. Biochim Biophys Acta Gen Subj 2012; 1820:643-51. [DOI: 10.1016/j.bbagen.2011.12.013] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 11/28/2011] [Accepted: 12/17/2011] [Indexed: 10/14/2022]
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Yoshie T, Nishiumi S, Izumi Y, Sakai A, Inoue J, Azuma T, Yoshida M. Regulation of the metabolite profile by an APC gene mutation in colorectal cancer. Cancer Sci 2012; 103:1010-21. [PMID: 22380946 DOI: 10.1111/j.1349-7006.2012.02262.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 02/22/2012] [Accepted: 02/26/2011] [Indexed: 11/28/2022] Open
Abstract
Mutation of the APC gene occurs during the early stages of colorectal cancer development. To obtain new insights into the mechanisms underlying the aberrant activation of the Wnt pathway that accompanies APC mutation, we carried out a gas chromatography-mass spectrometry-based semiquantitative metabolome analysis. In vitro experiments comparing SW480 cells expressing normal APC and truncated APC indicated that the levels of metabolites involved in the latter stages of the intracellular tricarboxylic acid cycle, including succinic acid, fumaric acid, and malic acid, were significantly higher in the SW480 cells expressing the truncated APC. In an in vivo study, we found that the levels of most amino acids were higher in the non-polyp tissues of APC(min/+) mice than in the normal tissues of the control mice and the polyp tissues of APC(min/+) mice. Ribitol, the levels of which were decreased in the polyp lesions of the APC(min/+) mice and the SW480 cells expressing the truncated APC, reduced the growth of SW480 cells with the APC mutation, but did not affect the growth of SW480 transfectants expressing full-length APC. The level of sarcosine was found to be significantly higher in the polyp tissues of APC(min/+) mice than in their non-polyp tissues and the normal tissues of the control mice, and the treatment of SW480 cells with 50 μM sarcosine resulted in a significant increase in their growth rate. These findings suggest that APC mutation causes changes in energetic metabolite pathways and that these alterations might be involved in the development of colorectal cancer.
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Affiliation(s)
- Tomoo Yoshie
- Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
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The failure to extend lifespan via disruption of complex II is linked to preservation of dynamic control of energy metabolism. Mitochondrion 2011; 12:280-7. [PMID: 22122855 DOI: 10.1016/j.mito.2011.10.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 10/14/2011] [Accepted: 10/28/2011] [Indexed: 11/21/2022]
Abstract
A decrease in mitochondrial electron transport chain (ETC) activity results in an extended lifespan in Caenorhabditis elegans. This longevity has only been reported when complexes I, III and IV genes are silenced, but not genes of complex II. We now have suppressed each complex II subunit in turn and have confirmed that in no case is lifespan extended. Animals with impaired complex II function exhibit similar metabolic changes to those observed following suppression of complexes I, III and IV genes, but the magnitude of the changes is smaller. Furthermore, an inverse correlation exists between mitochondrial membrane potential and ATP levels (r(2)=0.82), which strongly suggests that dynamic allocation of energy resources is maintained. In contrast, suppression of genes from complexes I, III and IV, results in a metabolic crisis with an associated stress response and loss of metabolic flexibility. Thus, the maintenance of a normal metabolism at a moderately decreased level does not alter normal lifespan, whereas metabolic crisis and induction of a stress response is linked to lifespan extension.
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32
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Zhou Q, Zhai Y, Lou J, Liu M, Pang X, Sun F. Thiabendazole inhibits ubiquinone reduction activity of mitochondrial respiratory complex II via a water molecule mediated binding feature. Protein Cell 2011; 2:531-42. [PMID: 21822798 DOI: 10.1007/s13238-011-1079-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 07/19/2011] [Indexed: 10/17/2022] Open
Abstract
The mitochondrial respiratory complex II or succinate: ubiquinone oxidoreductase (SQR) is a key membrane complex in both the tricarboxylic acid cycle and aerobic respiration. Five disinfectant compounds were investigated with their potent inhibition effects on the ubiquinone reduction activity of the porcine mitochondrial SQR by enzymatic assay and crystallography. Crystal structure of the SQR bound with thiabendazole (TBZ) reveals a different inhibitor-binding feature at the ubiquinone binding site where a water molecule plays an important role. The obvious inhibitory effect of TBZ based on the biochemical data (IC(50) ~100 μmol/L) and the significant structure-based binding affinity calculation (~94 μmol/L) draw the suspicion of using TBZ as a good disinfectant compound for nematode infections treatment and fruit storage.
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Affiliation(s)
- Qiangjun Zhou
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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Martins VDP, Dinamarco TM, Curti C, Uyemura SA. Classical and alternative components of the mitochondrial respiratory chain in pathogenic fungi as potential therapeutic targets. J Bioenerg Biomembr 2011; 43:81-8. [PMID: 21271279 DOI: 10.1007/s10863-011-9331-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The frequency of opportunistic fungal infection has increased drastically, mainly in patients who are immunocompromised due to organ transplant, leukemia or HIV infection. In spite of this, only a few classes of drugs with a limited array of targets, are available for antifungal therapy. Therefore, more specific and less toxic drugs with new molecular targets is desirable for the treatment of fungal infections. In this context, searching for differences between mitochondrial mammalian hosts and fungi in the classical and alternative components of the mitochondrial respiratory chain may provide new potential therapeutic targets for this purpose.
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Affiliation(s)
- Vicente de Paulo Martins
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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Simcock DC, Walker LR, Pedley KC, Simpson HV, Brown S. The tricarboxylic acid cycle in L₃ Teladorsagia circumcincta: metabolism of acetyl CoA to succinyl CoA. Exp Parasitol 2011; 128:68-75. [PMID: 21320492 DOI: 10.1016/j.exppara.2011.02.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 02/02/2011] [Accepted: 02/08/2011] [Indexed: 11/30/2022]
Abstract
Nematodes, like other species, derive much of the energy for cellular processes from mitochondrial pathways including the TCA cycle. Previously, we have shown L₃ Teladorsagia circumcincta consume oxygen and so may utilise a full TCA cycle for aerobic energy metabolism. We have assessed the relative activity levels and substrate affinities of citrate synthase, aconitase, isocitrate dehydrogenase (both NAD+ and NADP+ specific) and α-ketoglutarate dehydrogenase in homogenates of L₃ T. circumcincta. All of these enzymes were present in homogenates. Compared with citrate synthase, low levels of enzyme activity and low catalytic efficiency was observed for NAD+ isocitrate dehydrogenase and especially α-ketoglutarate dehydrogenase. Therefore, it is likely that the activity of these to enzymes regulate overall metabolite flow through the TCA cycle, especially when [NAD+] limits enzyme activity. Of the enzymes tested, only citrate synthase had substrate affinities which were markedly different from values obtained from mammalian species. Overall, the results are consistent with the suggestion that a full TCA cycle exists withinL₃ T. circumcincta. While there may subtle variations in enzyme properties, particularly for citrate synthase, the control points for the TCA cycle inL₃ T. circumcincta are probably similar to those in the tissues of their host species.
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Affiliation(s)
- D C Simcock
- Institute of Food Nutrition and Human Health, Massey University, Palmerston North 4442, New Zealand.
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35
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Nagaraj VA, Arumugam R, Prasad D, Rangarajan PN, Padmanaban G. Protoporphyrinogen IX oxidase from Plasmodium falciparum is anaerobic and is localized to the mitochondrion. Mol Biochem Parasitol 2010; 174:44-52. [PMID: 20603160 DOI: 10.1016/j.molbiopara.2010.06.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 05/21/2010] [Accepted: 06/24/2010] [Indexed: 11/19/2022]
Abstract
Earlier studies in this laboratory had shown that the malarial parasite can synthesize heme de novo and inhibition of the pathway leads to death of the parasite. It has been proposed that the pathway for the biosynthesis of heme in Plasmodium falciparum is unique involving three different cellular compartments, namely mitochondrion, apicoplast and cytosol. Experimental evidences are now available for the functionality and localization of all the enzymes of this pathway, except protoporphyrinogen IX oxidase (PfPPO), the penultimate enzyme. In the present study, PfPPO has been cloned, expressed and shown to be localized to the mitochondrion by immunofluorescence microscopy. Interestingly, the enzyme has been found to be active only under anaerobic conditions and is dependent on electron transport chain (ETC) acceptors for its activity. The native enzyme present in the parasite is inhibited by the ETC inhibitors, atovaquone and antimycin. Atovaquone, a well known inhibitor of parasite dihydroorotate dehydrogenase, dependent on the ETC, inhibits synthesis of heme as well in P. falciparum culture. A model is proposed to explain the ETC dependence of both the pyrimidine and heme-biosynthetic pathways in P. falciparum.
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36
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The electron transfer flavoprotein: ubiquinone oxidoreductases. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:1910-6. [PMID: 20937244 DOI: 10.1016/j.bbabio.2010.10.007] [Citation(s) in RCA: 161] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Revised: 07/20/2010] [Accepted: 10/05/2010] [Indexed: 12/30/2022]
Abstract
Electron transfer flavoprotein: ubiqionone oxidoreductase (ETF-QO) is a component of the mitochondrial respiratory chain that together with electron transfer flavoprotein (ETF) forms a short pathway that transfers electrons from 11 different mitochondrial flavoprotein dehydrogenases to the ubiquinone pool. The X-ray structure of the pig liver enzyme has been solved in the presence and absence of a bound ubiquinone. This structure reveals ETF-QO to be a monotopic membrane protein with the cofactors, FAD and a [4Fe-4S](+1+2) cluster, organised to suggests that it is the flavin that serves as the immediate reductant of ubiquinone. ETF-QO is very highly conserved in evolution and the recombinant enzyme from the bacterium Rhodobacter sphaeroides has allowed the mutational analysis of a number of residues that the structure suggested are involved in modulating the reduction potential of the cofactors. These experiments, together with the spectroscopic measurement of the distances between the cofactors in solution have confirmed the intramolecular pathway of electron transfer from ETF to ubiquinone. This approach can be extended as the R. sphaeroides ETF-QO provides a template for investigating the mechanistic consequences of single amino acid substitutions of conserved residues that are associated with a mild and late onset variant of the metabolic disease multiple acyl-CoA dehydrogenase deficiency (MADD).
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Tomitsuka E, Kita K, Esumi H. The NADH-fumarate reductase system, a novel mitochondrial energy metabolism, is a new target for anticancer therapy in tumor microenvironments. Ann N Y Acad Sci 2010; 1201:44-9. [DOI: 10.1111/j.1749-6632.2010.05620.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Lenaz G, Genova ML. Structure and organization of mitochondrial respiratory complexes: a new understanding of an old subject. Antioxid Redox Signal 2010; 12:961-1008. [PMID: 19739941 DOI: 10.1089/ars.2009.2704] [Citation(s) in RCA: 185] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The enzymatic complexes of the mitochondrial respiratory chain have been extensively investigated in their structural and functional properties. A clear distinction is possible today between three complexes in which the difference in redox potential allows proton translocation (complexes I, III, and IV) and those having the mere function to convey electrons to the respiratory chain. We also have a clearer understanding of the structure and function of most respiratory complexes, of their biogenesis and regulation, and of their capacity to generate reactive oxygen species. Past investigations led to the conclusion that the complexes are randomly dispersed and functionally connected by diffusion of smaller redox components, coenzyme Q and cytochrome c. More-recent investigations by native gel electrophoresis and single-particle image processing showed the existence of supramolecular associations. Flux-control analysis demonstrated that complexes I and III in mammals and I, III, and IV in plants kinetically behave as single units, suggesting the existence of substrate channeling. This review discusses conditions affecting the formation of supercomplexes that, besides kinetic advantage, have a role in the stability and assembly of the individual complexes and in preventing excess oxygen radical formation. Disruption of supercomplex organization may lead to functional derangements responsible for pathologic changes.
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Affiliation(s)
- Giorgio Lenaz
- Dipartimento di Biochimica "G. Moruzzi," Alma Mater Studiorum, Università di Bologna, Bologna, Italy.
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Paranagama MP, Sakamoto K, Amino H, Awano M, Miyoshi H, Kita K. Contribution of the FAD and quinone binding sites to the production of reactive oxygen species from Ascaris suum mitochondrial complex II. Mitochondrion 2009; 10:158-65. [PMID: 20006739 DOI: 10.1016/j.mito.2009.12.145] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Revised: 10/22/2009] [Accepted: 12/09/2009] [Indexed: 11/30/2022]
Abstract
Reactive oxygen species (ROS) production from mitochondrial complex II (succinate-quinone reductase, SQR) has become a focus of research recently since it is implicated in carcinogenesis. To date, the FAD site is proposed as the ROS producing site in complex II, based on studies done on Escherichia coli, whereas the quinone binding site is proposed as the site of ROS production based on studies in Saccharomyces cerevisiae. Using the submitochondrial particles from the adult worms and L(3) larvae of the parasitic nematode Ascaris suum, we found that ROS are produced from more than one site in the mitochondrial complex II. Moreover, the succinate-dependent ROS production from the complex II of the A. suum adult worm was significantly higher than that from the complex II of the L(3) larvae. Considering the conservation of amino acids crucial for the SQR activity and the high levels of ROS production from the mitochondrial complex II of the A. suum adult worm together with the absence of complexes III and IV activities in its respiratory chain, it is a good model to examine the reactive oxygen species production from the mitochondrial complex II.
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Affiliation(s)
- Madhavi P Paranagama
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Hirayama A, Kami K, Sugimoto M, Sugawara M, Toki N, Onozuka H, Kinoshita T, Saito N, Ochiai A, Tomita M, Esumi H, Soga T. Quantitative Metabolome Profiling of Colon and Stomach Cancer Microenvironment by Capillary Electrophoresis Time-of-Flight Mass Spectrometry. Cancer Res 2009; 69:4918-25. [DOI: 10.1158/0008-5472.can-08-4806] [Citation(s) in RCA: 717] [Impact Index Per Article: 47.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Elevated levels of urinary hydrogen peroxide, advanced oxidative protein product (AOPP) and malondialdehyde in humans infected with intestinal parasites. Parasitology 2009; 136:359-63. [PMID: 19154644 DOI: 10.1017/s0031182008005465] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Oxidative stress has been implicated as an important pathogenic factor in the pathophysiology of various life-threatening diseases such as cancer, cardiovascular diseases and diabetes. It occurs when the production of free radicals (generated during aerobic metabolism, inflammation, and infections) overcome the antioxidant defences in the body. Although previous studies have implied that oxidative stress is present in serum of patients with parasitic infection there have been no studies confirming oxidative stress levels in the Malaysian population infected with intestinal parasites. Three biochemical assays namely hydrogen peroxide (H2O2), lipid peroxidation (LP) and advanced oxidative protein product (AOPP) assays were carried out to measure oxidative stress levels in the urine of human subjects whose stools were infected with parasites such as Blastocystis hominis, Ascaris, Trichuris, hookworm and microsporidia. The levels of H2O2, AOPP and LP were significantly higher (P<0.001, P<0.05 and P<0.05 respectively) in the parasite-infected subjects (n=75) compared to the controls (n=95). In conclusion, the study provides evidence that oxidative stress is elevated in humans infected by intestinal parasites. This study may influence future researchers to consider free radical-related pathways to be a target in the interventions of new drugs against parasitic infection and related diseases.
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Tomitsuka E, Kita K, Esumi H. Regulation of succinate-ubiquinone reductase and fumarate reductase activities in human complex II by phosphorylation of its flavoprotein subunit. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2009; 85:258-265. [PMID: 19644226 PMCID: PMC3561849 DOI: 10.2183/pjab.85.258] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 06/22/2009] [Indexed: 05/28/2023]
Abstract
Complex II (succinate-ubiquinone reductase; SQR) is a mitochondrial respiratory chain enzyme that is directly involved in the TCA cycle. Complex II exerts a reverse reaction, fumarate reductase (FRD) activity, in various species such as bacteria, parasitic helminths and shellfish, but the existence of FRD activity in humans has not been previously reported. Here, we describe the detection of FRD activity in human cancer cells. The activity level was low, but distinct, and it increased significantly when the cells were cultured under hypoxic and glucose-deprived conditions. Treatment with phosphatase caused the dephosphorylation of flavoprotein subunit (Fp) with a concomitant increase in SQR activity, whereas FRD activity decreased. On the other hand, treatment with protein kinase caused an increase in FRD activity and a decrease in SQR activity. These data suggest that modification of the Fp subunit regulates both the SQR and FRD activities of complex II and that the phosphorylation of Fp might be important for maintaining mitochondrial energy metabolism within the tumor microenvironment.
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Affiliation(s)
- Eriko Tomitsuka
- Cancer Physiology Project, Investigative Treatment Division, National Cancer Center Research Institute East, Chiba, Japan.
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A soluble NADH-dependent fumarate reductase in the reductive tricarboxylic acid cycle of Hydrogenobacter thermophilus TK-6. J Bacteriol 2008; 190:7170-7. [PMID: 18757546 DOI: 10.1128/jb.00747-08] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fumarate reductase (FRD) is an enzyme that reduces fumarate to succinate. In many organisms, it is bound to the membrane and uses electron donors such as quinol. In this study, an FRD from a thermophilic chemolithoautotrophic bacterium, Hydrogenobacter thermophilus TK-6, was purified and characterized. FRD activity using NADH as an electron donor was not detected in the membrane fraction but was found in the soluble fraction. The purified enzyme was demonstrated to be a novel type of FRD, consisting of five subunits. One subunit showed high sequence identity to the catalytic subunits of known FRDs. Although the genes of typical FRDs are assembled in a cluster, the five genes encoding the H. thermophilus FRD were distant from each other in the genome. Furthermore, phylogenetic analysis showed that the H. thermophilus FRD was located in a distinct position from those of known soluble FRDs. This is the first report of a soluble NADH-dependent FRD in Bacteria and of the purification of a FRD that operates in the reductive tricarboxylic acid cycle.
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44
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Change of subunit composition of mitochondrial complex II (succinate–ubiquinone reductase/quinol–fumarate reductase) in Ascaris suum during the migration in the experimental host. Parasitol Int 2008; 57:54-61. [DOI: 10.1016/j.parint.2007.08.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Revised: 08/11/2007] [Accepted: 08/16/2007] [Indexed: 11/18/2022]
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Yu J, Wang S, Li W, Dai G, Xu S, He Z, Peng X, Zhou S, Liu X. Cloning, expression and protective immunity evaluation of the full-length cDNA encoding succinate dehydrogenase iron-sulfur protein of Schistosoma japonicum. ACTA ACUST UNITED AC 2007; 50:221-7. [PMID: 17447029 DOI: 10.1007/s11427-007-0035-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2006] [Accepted: 11/22/2006] [Indexed: 10/23/2022]
Abstract
1071-bp fragment was obtained from the Schistosoma japonicum (Chinese strain) adult cDNA library after the 3' and 5' ends of the incomplete expression sequence tag (EST) of succinate dehydrogenase iron-sulfur protein of Schistosoma japonicum (SjSDISP) were amplified by the anchored PCR with 2 pairs of primers designed according to the EST of SjSDISP and the sequence of multiclone sites of the library vector. Sequence analysis indicated that the fragment was a full-length cDNA with a complete open reading frame (ORF), encoding 278 amino acid residues. The fragment was cloned into prokaryotic expression vector pQE30, and subsequently sequenced and expressed in Escherichia coli. SDS-PAGE and Western-blot analyses showed that the recombinant protein was about 32 kD and could be recognized by the polyclonal antisera from rabbits immunized with Schistosoma japonicum adult worm antigen. Compared with the FCA controls, mice vaccinated with rSjSDISP (test) or rSjGST (positive control) all revealed high levels of specific antibody and significant reduction in worm burden, liver eggs per gram (LEPG), fecal eggs per gram (FEPG) and intrauterine eggs. These results suggest that SjSDISP may be a novel and partially protective vaccine candidate against schistosomiasis. In contrast to the worm burden reduction rate, the higher degree of egg reduction rate in the test group also suggested that SjSDISP vaccine may primarily play a role in anti-embryonation or anti-fecundity immunity.
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Affiliation(s)
- JunLong Yu
- Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha 410078, China
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46
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Fisher N, Bray PG, Ward SA, Biagini GA. The malaria parasite type II NADH:quinone oxidoreductase: an alternative enzyme for an alternative lifestyle. Trends Parasitol 2007; 23:305-10. [PMID: 17499024 DOI: 10.1016/j.pt.2007.04.014] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Revised: 03/27/2007] [Accepted: 04/26/2007] [Indexed: 10/23/2022]
Abstract
The operation of a type II NADH:quinone oxidoreductase (PfNDH2), also known as alternative Complex I, in the mitochondrion of the human malaria parasite, Plasmodium falciparum, has recently been described. Unlike the Complex I of typical mitochondria, type II NADH:quinone oxidoreductases do not have transmembrane domains and are not involved directly in proton (H(+)) pumping. Here, we present a predictive model of PfNDH2, describing putative NADH-, flavin- and quinone-binding sites, as well as a possible membrane 'anchoring' region. In addition, we hypothesize that the alternative Complex I is an evolutionary adaptation to a microaerophilic lifestyle enabling (proton) uncoupled oxidation of NADH. This adaptive feature has several advantages, including: (i) a reduction of proton 'back-pressure' in the absence of extensive ATP synthesis; (ii) a reduction of mitochondrial superoxide generation; and (iii) a mechanism for the deregulated oxidation of cytosolic NADH.
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Affiliation(s)
- Nicholas Fisher
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
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Ichimiya H, Huet RG, Hartman P, Amino H, Kita K, Ishii N. Complex II inactivation is lethal in the nematode Caenorhabditis elegans. Mitochondrion 2005; 2:191-8. [PMID: 16120320 DOI: 10.1016/s1567-7249(02)00069-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2002] [Revised: 08/15/2002] [Accepted: 08/21/2002] [Indexed: 10/27/2022]
Abstract
RNA-mediated interference (RNAi) was employed to systematically inactivate the four subunits of complex II in the mitochondrial electron transport chain. Embryonic lethality was the predominant result of inactivating three subunits (ceSDHB, ceSDHC, and ceSDHD) when using the soaking method to inactivate RNA. The feeding method was employed to deliver dsRNA from the fourth subunit (ceSDHA) to wild-type, mev-1 (mutated in ceSDHC of complex II), and gas-1 animals (mutated in a complex I gene). Survival was reduced only in the mev-1 genetic background, and in an oxygen-dependent fashion. Collectively, these data provide further evidence that compromised complex II integrity can result in sensitivity to oxidative stress.
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Affiliation(s)
- Harumi Ichimiya
- Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Kanagawa 259-1193, Japan
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del Arenal IP, Rubio ME, Ramírez J, Rendón JL, Escamilla JE. Cyanide-resistant respiration in Taenia crassiceps metacestode (cysticerci) is explained by the H2O2-producing side-reaction of respiratory complex I with O2. Parasitol Int 2005; 54:185-93. [PMID: 15958286 DOI: 10.1016/j.parint.2005.04.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2004] [Accepted: 04/14/2005] [Indexed: 11/29/2022]
Abstract
The nature of the cyanide-resistant respiration of Taenia crassiceps metacestode was studied. Mitochondrial respiration with NADH as substrate was partially inhibited by rotenone, cyanide and antimycin in decreasing order of effectiveness. In contrast, respiration with succinate or ascorbate plus N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) was more sensitive to antimycin and cyanide. The saturation kinetics for O2 with NADH as substrate showed two components, which exhibited different oxygen affinities. The high-O2-affinity system (Km app=1.5 microM) was abolished by low cyanide concentration; it corresponded to cytochrome aa3. The low-O2-affinity system (Km app=120 microM) was resistant to cyanide. Similar O2 saturation kinetics, using succinate or ascorbate-TMPD as electron donor, showed only the high-O2-affinity cyanide-sensitive component. Horse cytochrome c increased 2-3 times the rate of electron flow across the cyanide-sensitive pathway and the contribution of the cyanide-resistant route became negligible. Mitochondrial NADH respiration produced significant amounts of H2O2 (at least 10% of the total O2 uptake). Bovine catalase and horse heart cytochrome c prevented the production and/or accumulation of H2O2. Production of H2O2 by endogenous respiration was detected in whole cysticerci using rhodamine as fluorescent sensor. Thus, the CN-resistant and low-O2-affinity respiration results mainly from a spurious reaction of the respiratory complex I with O2, producing H2O2. The meaning of this reaction in the microaerobic habitat of the parasite is discussed.
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Affiliation(s)
- I Patricia del Arenal
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Apartado postal 70-159, México 04510 D.F., México.
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Keithly JS, Langreth SG, Buttle KF, Mannella CA. Electron tomographic and ultrastructural analysis of the Cryptosporidium parvum relict mitochondrion, its associated membranes, and organelles. J Eukaryot Microbiol 2005; 52:132-40. [PMID: 15817118 DOI: 10.1111/j.1550-7408.2005.04-3317.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Sporozoites of the apicomplexan Cryptosporidium parvum possess a small, membranous organelle sandwiched between the nucleus and crystalloid body. Based upon immunolabelling data, this organelle was identified as a relict mitochondrion. Transmission electron microscopy and tomographic reconstruction reveal the complex arrangement of membranes in the vicinity of this organelle, as well as its internal organization. The mitochondrion is enveloped by multiple segments of rough endoplasmic reticulum that extend from the outer nuclear envelope. In tomographic reconstructions of the mitochondrion, there is either a single, highly-folded inner membrane or multiple internal subcompartments (which might merge outside the reconstructed volume). The infoldings of the inner membrane lack the tubular "crista junctions" found in typical metazoan, fungal, and protist mitochondria. The absence of this highly conserved structural feature is congruent with the loss, through reductive evolution, of the normal oxidative phosphorylation machinery in C. parvum. It is proposed that the retention of a relict mitochondrion in C. parvum is a strategy for compartmentalizing away from the cytosol toxic ferrous iron and sulfide, which are needed for iron sulfur cluster biosynthesis, an essential function of mitochondria in all eukaryotes.
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Affiliation(s)
- Janet S Keithly
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, New York 12201, USA.
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Nakada T, Nagano I, Wu Z, Takahashi Y. Molecular cloning and functional expression of enolase from Trichinella spiralis. Parasitol Res 2005; 96:354-60. [PMID: 15928906 DOI: 10.1007/s00436-005-1365-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Accepted: 03/22/2005] [Indexed: 10/25/2022]
Abstract
The cDNA library was constructed from muscle larvae of Trichinella spiralis, and immunoscreened with sera from mice infected with T. spiralis. A cDNA clone, designated as TsENO, encoded 2-phospho-D-glycerate hydro-lyase (enolase) that catalyzed a reversible conversion of 2-phospho-D-glyceric acid (2PGA) to phosphoenolpyruvate (PEP) in the glycolytic pathway. The recombinant TsENO protein was produced in an Escherichia coli expression system. The recombinant full-length TsENO protein had no activity in the conversion of 2PGA to PEP, but gained enolase activity after cutting off the signal peptide from the full-length protein. There was no meaningful difference in the expression level of TsENO gene at three distinct stages of T. spiralis. Also, antibody against the recombinant TsENO protein reacted with crude extract of muscle larvae, but not with the excretory and secretory products.
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Affiliation(s)
- T Nakada
- Department of Parasitology, Gifu University Graduate School of Medicine, Yanagido 1-1, Gifu 501-1194, Japan
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